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Bartender Sam Trasatti said two guys who appeared to be in their 30s came in Thursday night and ordered drinks, brandishing an Amex Black Card. "They were good-looking, dressed average, nice," she said. "But people who pay with a Black Card aren't usually good tippers."

When they went outside to eat dinner, she transferred their tab to the waitress working that table, as is customary.

After their meal, Trasatti said, the waitress, Jess Nguyen, noticed that a tip for $5,000 had been added to the men's $258 check, alongside the words "God bless!!" and "Boom!!!" (They ordered the signature Rouge burger, a cheese plate and a decent amount of alcohol, including a $110 bottle of Perrier-Jouët.)

"They were messing with me throughout the meal, asking if I ever heard of Tips for Jesus," Nguyen said. "We really busy last night and I didn't have a second to breathe. They kept asking me questions like, 'If something amazing happened to you, who is the first person you'd call?' and 'On a scale of 1 to 10, how crazy are we as customers?' "

They sent the bottle of bubbly to two women and insisted that Nguyen keep the donor's ID private.

Nguyen said they also told her, "Don't worry. We're going to tip you well."

Did they ever.

"When he wrote down the tip, to be honest with you, it didn't feel real," Nguyen said.

"I was OK, this is real. I almost peed my pants and nearly started crying," Nguyen said. "I had butterflies in my stomach."

"I feel like I won the lottery," she said.

Staff went into a tizzy when word spread.

Trasatti, who has worked at Rouge for six years and is also a personal trainer (and a 2012 "Sexy Single" from the Philadelphia Daily News), said a few fellow servers grumbled at Nguyen's good fortune because she is a new hire, having joined the restaurant in February after five years out of the restaurant business. (The restaurant does not pool tips.)

As the hubbub died down, the two men reappeared at Trasatti's post, asking if she had heard what happened. "I tried to play it cool, but I said, 'Yeah.' "

Then she said, "You know ... I'd be happy with just a thousand."

The guys left Trasatti $2,000 on a $150 bar tab, adding a "God bless!!" next to the tip line.

Nguyen, who also is an English as a second language teacher, wants to use her $5,000 toward additional teaching certification.

Trasatti said she is not sure what she will do with her windfall. "I'm turning 30, so maybe I'll use it to go to Europe," she said.

So who is this "Tips for Jesus" guy? Who knows. He scratched out his name on the credit-card receipt, but reports say he is Jack Shelby, a San Francisco-based financier and former executive with PayPal.